Police mistreatment of communities of color has caused “multi-generational” mistrust of law enforcement, says the organization's president.

Against a backdrop of outrage over the police killings of unarmed Black men, the president of one of the nation’s largest police organizations apologized Monday for law enforcement’s historic mistreatment of minorities, NBC News reports.

Terrence Cunningham, president of the International Association of Chiefs of Police, said those types of shootings have a long history in this country and have created a legacy of “multi-generational, almost inherited” mistrust of the police.

Cunningham’s statement, which came at the organization’s annual conference in San Diego, surprised many. Even with this public spate of video-recorded police involved killings, law enforcement officials often deny systemic injustice and responsibility for causing poor relationships with communities of color.

In a statement, the Rev. Al Sharpton of the National Action Network welcomed the apology and called on Cunningham to “urge officers around the United States to back his words up with action and legislation to protect communities of color from the onslaught of police misconduct that has disturbed the country.”

Cunningham, who serves as police chief of Wellesley, Massachusetts, apparently understood that many would view his organization’s apology as mere symbolism. But he said that it’s possible to improve the damaged relationship.

As a first step, he urged law enforcement to “acknowledge and apologize” for past mistreatment of minorities. He also called on the mistreated communities to give officers a chance, because today’s police force is not guilty of the historic misdeeds.

“If either side in this debate fails to acknowledge these fundamental truths, we will be unlikely to move past them,” he said.